1. Field of the Invention
The present invention relates generally to centrifugal type slicing apparatus. More specifically the present invention relates to a replaceable blade cartridge for use in a centrifugal type slicer, especially for slicing potatoes, wherein one cartridge may be slidably removed from a cutting head assembly and a new cartridge slidably inserted into the cutting head assembly.
2. Description of Related Art
The commercial process of processing vegetables, nuts, and fruit requires sized reduction of large volumes of food stuffs. The present invention will be described in terms of slicing potatoes to make potato chips. However, as those skilled in the art will appreciate, the present invention can be employed for a wide variety of uses such as shredding or producing a variety of geometrical shapes. Various machines have been developed to accomplish the potato slicing.
One such machine is a centrifugal type slicer, such as the Urschell Model CC Slicer, manufactured by Urschell Laboratories, Inc. In this slicer an impeller with inwardly extending partitions is rotated and potatoes are placed in the impeller. The centrifugal force created by the rotating impeller forces the potatoes outwardly against the partitions and a cutting head surrounding the impeller. The cutting head is generally cylindrical shaped and includes a series of related cutting blades spaced around the cutting head and separated by curved supporting walls, commonly referred to as shoes.
A typical cutting head includes eight shoes and blades and is fitted onto the slicer by a series of locating pins. Each shoe holds a cutting blade and has a pivoting pin that is inserted into a corresponding hole on a retaining ring. The shoes are then rotatable about this pivoting pin and are attached to the ring by a screw.
In use a blade becomes dull and needs frequent replacement. Therefore, each typical head requires that eight blades be replaced many times during operation and typically there are multiple heads feeding subsequent processing units. To replace the blades, the head must be lifted from the slicer and turned over so that the head rests on the retaining ring. Next, bolts on a blade clamp are loosened or removed to allow the blade to be removed from the blade holder. After a new blade is inserted and the blade clamp tightened to hold the blade in place each shoe must be adjusted relative to its two adjacent shoes. This adjustment is necessary in order to maintain a constant predetermined slice thickness.
The adjustment is made by first loosening the screw holding the shoe to the ring to allow the shoe to be pivoted. Next, a setting gauge measures the gap between the new blade and the adjacent shoe. This gap determines the thickness of each potato slice and ideally should be maintained at uniform spacing. This gap is not always set to the same thickness because different density potatoes need to be set at different gap thicknesses. If the potatoes are "heavy", i.e. contain less water, the gap needs to be narrower than for less heavy potatoes because the slices will shrink less than "lighter" slices. Also, the operator must allow for a fluctuation in the gap thickness when he tightens down each shoe. A skilled operator may have to make up to 10 gap adjustments for an eight blade cutting head, before the proper gap tolerances are achieved, and those less skilled may have to make more.
Therefore, it can be seen that it is time consuming and difficult to set the gaps in the cutting head. It can take a skilled operator as much as ten minutes to change blades and adjust the gap thickness on a single cutting head.
Due to the pivoting feature of the shoes there is a certain amount of movement and give in the shoes. This results in uncontrollable variability in the slice thickness of the potatoes. Wear at the junction of the pivoting pin and the hole in the retaining ring results in the shoes being movable within the cutting head assembly and introduces an even greater amount of variability in slice thickness. When a potato contacts a shoe during slicing the potato may cause one or more of the cutting shoes to move resulting in a potato slice which is not within an acceptable range of thickness.
Another problem is encountered because the shoes are connected to only one retaining ring on one side of the shoe. When the pivot junction begins to wear this may result in a non-uniform gap thickness from the retaining ring to a point opposite the ring. This is highly undesirable in a commercial setting where a uniform potato slice is necessary to maintain a high level of quality control in the end product--potato chips.